Current injector circuit for supplying a load transient in an integrated circuit

• US 8,164,321 B2
• Filed: 03/09/2010
• Issued: 04/24/2012
• Est. Priority Date: 03/09/2010
• Status: Active Grant

• Current Assignee: NXP USA, Inc. (NXP Semiconductors NV)
• Original Assignee: Freescale Semiconductor, Inc. (NXP Semiconductors NV)
• Inventors: Choy, Jon S.
• Primary Examiner(s): Laxton, Gary L
• Application Number:
  US12/720,304
• Publication Number:
  US 20110221410A1
• Time in Patent Office: 777 Days
• Field of Search: 323/267, 323/283, 323/299, 323/312, 323/316, 323/317, 365/189.011, 365/189.09, 365/226, 327/538
• US Class Current: 323/317
• CPC Class Codes: G11C 5/145 Applications of charge pumps; Boosted voltage circuits; Clamp circuits therefor G11C5/141 takes precedence
• CPC Class Codes: G11C 8/10 Decoders
• CPC Class Codes: H03K 19/01728 in synchronous circuits, i.e. by using clock signals

Abstract

A current injector circuit comprises a clock modulating circuit, a first current injector, a feedback circuit, a first input modulating circuit and a second current injector. The clock modulating circuit receives a clock, a control signal, and an output. The first current injector has an input coupled to the clock modulating circuit, and an output coupled to a power supply terminal for providing a first current. The feedback circuit is coupled between the power supply terminal and another input of the clock modulating circuit. The feedback circuit is for providing the control signal for controlling the clock modulating circuit. The first current injector provides the first current in response to the clock modulating circuit. The first input modulating circuit receives an input signal, the control signal, and an output. The second current injector has an input coupled to the first input modulating circuit, and an output for providing a second current.

Claims

1. A current injector circuit comprising:

a clock signal modulating circuit having a first input for receiving a clock signal, a second input for receiving a control signal, and an output;

a first current injector having an input coupled to the output of the clock signal modulating circuit, and an output coupled to a power supply voltage terminal for providing a first predetermined current;

a feedback circuit coupled between the power supply voltage terminal and a second input of the clock modulating circuit, the feedback circuit for providing the control signal for controlling the clock modulating circuit, and in response, the first current injector for providing the first predetermined current;

a first input signal modulating circuit having a first input for receiving an input signal, a second input for receiving the control signal, and an output; and

a second current injector having an input coupled to the output of the first input signal modulating circuit, and an output for providing a second predetermined current.

2. The current injector circuit of claim 1, wherein the feedback circuit comprises:

a voltage divider coupled to the power supply voltage terminal; and

a differential amplifier having a first input coupled to the voltage divider, a second input coupled to receive a reference voltage, and an output coupled to the second inputs of the both the clock signal modulating circuit and the first input signal modulating circuit.

3. The current injector circuit of claim 2, wherein the voltage divider comprises a first variable resistance and a second variable resistance, the first and second variable resistances coupled between the power supply voltage terminal and a second power supply voltage terminal.

4. The current injector circuit of claim 1, further comprising:

a second input signal modulating circuit having a first input for receiving the input signal, a second input for receiving the control signal, and an output coupled to the output of the first input signal modulating circuit; and

a third current injector having an input coupled to the output of the second input signal modulating circuit, and an output coupled to the output of the first input signal modulating circuit, the second and third current injectors both providing the second predetermined current.

5. The current injector circuit of claim 1, wherein the second predetermined current is a multiple of the first predetermined current.

6. The current injector circuit of claim 1, wherein the second current injector comprises:

a first transistor having a first current electrode coupled to the output of the second current injector, a control electrode, and a second current electrode;

a second transistor having a first current electrode coupled to the second current electrode of the first transistor, a control electrode coupled to the control electrode of the first transistor, and second current electrode coupled to a second power supply voltage terminal; and

a capacitor having a first plate electrode coupled to the second current electrode of the first transistor, and a second plate electrode coupled to the output of the first input signal modulating circuit.

7. The current injector circuit of claim 1, wherein the first current injector comprises:

a first transistor having a first current electrode coupled to the output of the first current injector, a control electrode, and a second current electrode;

a second transistor having a first current electrode coupled to the second current electrode of the first transistor, a control electrode coupled to the control electrode of the first transistor, and second current electrode coupled to a second power supply voltage terminal; and

a capacitor having a first plate electrode coupled to the second current electrode of the first transistor, and a second plate electrode coupled to the output of the clock signal modulating circuit.

8. A current injector circuit comprising:

a differential amplifier having a first input terminal coupled to a first supply voltage terminal, a second input terminal coupled to receive a reference voltage, and an output terminal;

a clock modulating circuit having a first input terminal coupled to the output terminal of the differential amplifier, a second input terminal coupled to receive a clock signal, and an output terminal;

a master current injector having an input terminal coupled to the output terminal of the clock modulating circuit, and an output terminal coupled to the first supply voltage terminal;

a first input modulating circuit having a first input terminal coupled to the output terminal of the differential amplifier, a second input terminal coupled to receive an input signal, and an output terminal; and

a first slave current injector having an input terminal coupled to the output terminal of the first input modulating circuit, and an output terminal for supplying an output current.

9. The current injector circuit of claim 8, wherein the first input terminal of the differential amplifier is coupled to the first supply voltage terminal through a voltage divider.

10. The current injector circuit of claim 8, wherein the clock modulating circuit comprises:

a first transistor having a first current electrode coupled to a second power supply voltage terminal, a control electrode coupled to the output terminal of the differential amplifier, and a second current electrode;

a second transistor having a first current electrode coupled to the second current electrode of the first transistor, a control electrode couple to receive the clock signal, and a second current electrode coupled to the input terminal of the master current injector; and

a third transistor having a first current electrode coupled to the second current electrode of the second transistor, a control electrode coupled to receive the clock signal, and a second current electrode coupled to a third supply voltage terminal.

11. The current injector circuit of claim 8, wherein the master current injector comprises:

a first transistor having a first current electrode coupled to the output of the master current injector, a control electrode, and a second current electrode;

a second transistor having a first current electrode coupled to the second current electrode of the first transistor, a control electrode coupled to the control electrode of the first transistor, and second current electrode coupled to a second supply voltage terminal; and

a capacitor having a first plate electrode coupled to the second current electrode of the first transistor, and a second plate electrode coupled to the output terminal of the clock signal modulating circuit.

12. The current injector circuit of claim 8, wherein the first slave current injector comprises:

a first transistor having a first current electrode coupled to the output of the first slave current injector, a control electrode, and a second current electrode;

a second transistor having a first current electrode coupled to the second current electrode of the first transistor, a control electrode coupled to the control electrode of the first transistor, and second current electrode coupled to a second supply voltage terminal; and

a capacitor having a first plate electrode coupled to the second current electrode of the first transistor, and a second plate electrode coupled to the output terminal of the first input modulating circuit.

13. The current injector circuit of claim 8, wherein the output terminal of the first slave current injector is coupled to a word line of a memory.

14. The current injector circuit of claim 8, further comprising:

a second input modulating circuit having a first input terminal coupled to the output terminal of the differential amplifier, a second input terminal coupled to receive the input signal, and an output terminal; and

a second slave current injector having an input terminal coupled to the output terminal of the second input modulating circuit, and an output terminal for supplying the output current.

15. The current injector circuit of claim 8, wherein the current injector circuit is used in an analog-to-digital converter.

16. A current injector circuit comprising:

a clock signal modulating circuit having a first input for receiving a clock signal, a second input for receiving a control signal, and first and second outputs;

a first current injector comprising;

a first pair of cross-coupled inverters having first and second storage nodes, a power supply terminal for receiving a first power supply voltage, and an output terminal for providing a first predetermined current;

a first capacitor having a first plate electrode coupled to the first storage node, and a second plate electrode coupled to the first output of the clock signal modulating circuit; and

a second capacitor having a first plate electrode coupled to the second storage node, and a second plate electrode coupled to the second output of the clock signal modulating circuit;

a feedback circuit coupled between the output terminal of the first pair of cross-coupled inverters and the second input of the clock signal modulating circuit, the feedback circuit providing the control signal for controlling the clock modulating circuit, and in response, the first current injector providing the first predetermined current;

an input signal modulating circuit having a first input for receiving an input signal, a second input for receiving the control signal, and first and second outputs; and

a second current injector comprising;

a second pair of cross-coupled inverters having first and second storage nodes, a power supply terminal for receiving the first power supply voltage, and an output terminal for providing a second predetermined current;

a third capacitor having a first plate electrode coupled to the first storage node of the second pair of cross-coupled inverters, and a second plate electrode coupled to the first output of the input signal modulating circuit; and

a fourth capacitor having a first plate electrode coupled to the second storage node of the second pair of cross-coupled inverters, and a second plate electrode coupled to the second output of the input signal modulating circuit.

17. The current injector of claim 16, wherein the clock signal modulating circuit comprises:

a first transistor having a first current electrode coupled to receive the first power supply voltage, a control electrode coupled to receive the control signal, and a second current electrode;

a second transistor having a first current electrode coupled to the second current electrode of the first transistor, a control electrode couple to receive the clock signal, and a second current electrode coupled to the second plate electrode of the first capacitor; and

a third transistor having a first current electrode coupled to the second current electrode of the second transistor, a control electrode coupled to receive the clock signal, and a second current electrode coupled to receive a second power supply voltage.

18. The current injector circuit of claim 16, wherein the feedback circuit comprises:

a voltage divider coupled to the output terminal of the first pair of cross-coupled inverters; and

a differential amplifier having a first input coupled to the voltage divider, a second input coupled to receive a reference voltage, and an output coupled to the second inputs of the both the clock signal modulating circuit and the first input signal modulating circuit.

19. The current injector circuit of claim 16, wherein the output terminal of the second pair of cross-coupled inverters is coupled to a word line in a memory.

20. The current injector circuit of claim 16, wherein the regulated current injector circuit is used in an analog-to-digital converter.